In a WDR the Falcon 9 is rolled out, fueled and the countdown run down to the very moment before engine ignition. Then the tanks are drained, the F9 is rolled back to the hangar and everything is checked out. Later another rehearsal will include a "hot-fire" - a 3-4 second engine burn to check them out too. This usually tales place a few days before launch. During the recent WDR the Dragon and its cargo trunk were not attached, but they likely will be for the hot-fire.

Non-ISS cargo for this flight will include a prototype ORBCOMM OG2 communications satellite built by Sierra Nevada Corp. (also builders of the Dream Chaser spaceplane.) If all goes well 17 more ORBCOMM's will be lofted on later F9 flights.

This will be the next to last flight for the Falcon 9 v1.0 before the much larger and powerful Falcon 9 v1.1 comes into service. The F9 v1.1 will also be the core stage of the monster Falcon Heavy.

NASA and SpaceX have announced October 7, 2012 as the target launch date for SpaceX’s first resupply mission to the International Space Station (ISS). The launch of the Falcon 9 rocket and Dragon spacecraft is scheduled for 8:34 p.m. EDT from Cape Canaveral, Florida. October 8 is the backup date.

The launch represents the first of 12 SpaceX flights to the ISS under NASA’s Commercial Resupply Services (CRS) contract, and follows a successful demonstration mission in May when SpaceX became the first private company ever to attach to the ISS and return safely to Earth.

The SpaceX CRS-1 mission also represents restoration of American capability to deliver and return cargo to the ISS—a feat not achievable since the retirement of the space shuttle. SpaceX is also contracted to develop Dragon to send crew to the space station. SpaceX’s first manned flight is expected to take place in 2015.

On this mission, Dragon will be filled with supplies, which include materials to support 166 experiments in plant cell biology, human biotechnology, and materials technology. One experiment will examine the effects of microgravity on the opportunistic yeast Candida albicans, which is present on all humans. Another will evaluate how microgravity affects the growth of cell walls in a plant called Arabidopsis.

Expedition 33 Commander Sunita Williams of NASA and Aki Hoshide of the Japan Aerospace Exploration Agency will use a robotic arm to grapple Dragon following its rendezvous with the station, expected on October 10. They will attach Dragon to the Earth-facing port of the station’s Harmony module for a few weeks while crew members unload cargo and load experiment samples for return to Earth.

Dragon is scheduled to return in late October for a parachute-assisted splashdown in the Pacific Ocean off the coast of southern California. Dragon will fly back carrying scientific materials and space station hardware.

SpaceX says it successfully test-fired the engines on its Falcon 9 rocket today in preparation for Oct. 7's scheduled liftoff of the California-based company's first official cargo delivery to the International Space Station.

The static-fire test at Cape Canaveral Air Force Station in Florida was considered the "last major test" in advance of the launch, SpaceX said in a Twitter update. The rocket was held down while its nine Merlin engines blazed for a couple of seconds on the pad, at the end of a computer-controlled fueling sequence. Data from the test will be analyzed in advance of the scheduled launch at 8:34 p.m. ET on Oct. 7.

After the next flight (CRS-2 / SPX-2) the next launch will be from Vandenberg AFB using the upgraded Falcon 9 v1.1 - a much larger (229' v 157') and more powerful beast. The engine mounting is also changed from a 3x3 grid to an octagon with a center engine.

SpaceX Facebook -

Early in the morning, the Falcon 9 rocket and Dragon spacecraft rolled out to the launch pad. Engineers now complete final preparations for launch, targeted for 8:35PM ET tonight.